This study involves purification of cytolytic toxins from organisms of importance in corneal infections (e.g. Streptococcus pneumoniae and pseudomonas aeruginosa) and an assessment of the role of these agents in pathogenicity. The mechanism of action of these toxins and their response to various types of inhibitors will also be investigated. BIBLIOGRAPHIC REFERENCE: Johnson, Mary K. and James H. Allen 1975. The role of cytolysin in pneumococcal ocular infection. Amer. J. of Ophthalmology, 80 (Part II), 518-521.